Time delay apparatus with in-line construction for bi-directional flow



March 8, 196 w, LUDWIG 3,238,964

TIME DELAY APPARATUS WITH IN'LINE CONSTRUCTION FOR BI-DIRECTIONAL FLOW Filed April 29, 1963 3 Sheets-Sheet 1 FIG- I4- FiG.9

INVENTOR. WALTER D. LUDWIG ATTORNEYS March 8, 1965 LUDWIG 3,238,964

TIME DELAY APPARATUS WITH IN-LINE CONSTRUCTION FOR BI-DIREGTIONAL FLOW Filed April 29, 1963 3 Sheets-Sheet 2 FIGQ5.

INVENTOR. WALTER D. LUDWIG ,gi. U; I *W ATTO RN E (S March 8, 196% LUDW|G 3,238,964

TIME DELAY APPARATUS WITH IN-LINE CONSTRUCTION FOR BI-DIRECTIONAL FLOW Filed April 29, 1963 3 Sheets-Sheet 5 FIG- 7:

FIG- 6- 8 .Q d I m in 07 (D I 174 I (2 D1 5 I u m a INVENTOR.

4 P gm WALTER D.LUDWIG 0 a 8 N BY 0 N O (n O Q N fimfl W ATTORNEYS United States Patent 3,238,964 TIME DELAY APPARATUS WITH IN-LINE CON- STRUCTION FOR BI-DIRECTIONAL FLOW Walter D. Ludwig, 3865 Lincoln Drive, Bloomfield Township, Oakland County, Mich. Filed Apr. 29, 1963, Ser. No. 276,530 11 Claims. (Cl. 137-220) This invention relates generally to time delay apparatuses for controlling the flow of pressurized fluid in a fluid circuit, and more particularly to a time delay air apparatus incorporating an in-line construction and which is adapted to function independent of any valve and which can be used at any point in a pressurized fluid circuit exclusive of an operative valve.

The prior art time delay air units incorporate the time delay structure as an integral part of an operating valve and the prior art delay air units can only be employed with the specific incorporated operating valve structure. This is a disadvantage because in order to get a time delay function in a pressurized fluid circuit, it is necessary to purchase a certain and often undesired attached operating valve. A further disadvantage of the prior art time delay units is that they require disassembly and adjustment when they are changed from a timing-in to a timing-out operating position, and the same requirements must be met when reversing the aforementioned connection. Another disadvantage of the prior art time delay air units is that the time delay period is governed or controlled by the particular type of valve with which it is combined, whereby the versatility of the time delay unit is restricted. Still another disadvantage of the existing time delay air units is that they are constructed with dead end passageways which normally collect contaminants carried by the pressurized fluid. A further disadvantage of prior art time delay units is that the timing sequence tends to vary greatly as the system pressure fluctuates.

Accordingly, it is an important object of the present invention to provide a time delay unit which is adapted to be used in any pressurized fluid circuit, exclusive of an operating valve, and which can be changed from a timing-in to a timing-out operation and which can be adjusted to various desired time delay periods without disassembling the time delay unit.

It is another object of the present invention to provide a novel and improved time delay unit for use in pressurized fluid circuits and which may be connected in such circuits between a directional flow control valve and a fluid cylinder or valve to provide timing-in operations, or timing-out operations wherein the timing-out cycle is not started until the pressure is released at the primary source, and which can be further employed in a pressurized fluid circuit for timing fluid flow in only one direction, and providing free flow of the fluid in the other direction.

It is a further object of the present invention to provide a novel and improved time delay unit which may be used in any pressurized fluid circuit but which is especially adapted for use in pressurized air circuits, and which includes a body having a control chamber in one end thereof, a free flow chamber in the other end thereof, a valve bore connecting said chambers, a flow valve in said control chamber for engagement with said valve bore for controlling fluid flow therethrough, means for normally maintaining said flow valve in a closed position in seating engagement with said valve bore, accumulator means for unseating and moving said flow valve to an open position, pressurized fluid metering means for admitting a metered flow of said fluid into said accumulator means for operating the same in predetermined timed cycles for timing the opening and 3,238,954 Patented Mar. 8, I966 closing of said flow valve to provide a delayed flow of pressurized fluid through the chambers when the fluid moves through the valve bore in one direction, and a free flow of pressurized fluid through the chambers when the fluid moves through the valve bore in the opposite direction.

It is still a further object of the present invention to provide a novel and improved time delay unit that is not susceptible to variations in timing sequence due to fluctuations in system pressures since such variations are overcome by maintaining a constant relationship between the system pressure and the pressure require-d to open the flow valve, and by utilizing the same system pressure which acts to oppose the opening of the flow valve as the source of metered pressure for the accumulator means for opening the flow valve so that a variation in the system pressure produces a compensating variation in the rate of metered flow to the accumulator means.

Other objects, features and advantages of this invention will be apparent from the following detailed description and appended claims, reference being had to the accompanying drawings forming a part of the specification.

In the drawings:

FIG. 1 is a side elevational view of a time delay apparatus made in accordance with the principles of the present invention;

FIG. 2 is a left end elevational view of the structure illustrated in FIG. 1;

FIG. 3 is an enlarged central elevational sectional view of the structure illustrated in FIG. 2, taken along the line 3-3 thereof and looking in the direction of the arrows;

FIG. 4 is a fragmentary view of the right end structure of FIG. 3 and showing the time delay flow valve moved to the left, as viewed in FIG. 3, to permit free flow through the time delay apparatus;

FIG. 5 is a top plan view of the time delay apparatus illustrated in FIG. 1, with the metering device removed;

FIG. 6 is a central longitudinal elevational sectional view of the structure illustrated in FIG. 5, taken along the line 66 thereof, looking in the direction of the arrows, and showing the time delay apparatus body with the metering device and flow valve structure removed;

FIG. 7 is a right end elevational view of the structure illustrated in FIG. 6;

FIG. 8 is an elevational sectional view of the structure illustrated in FIG. 6, taken along the line 3-8 thereof and looking in the direction of the arrows;

FIG. 9 is a top plan View of the metering valve body employed in the invention;

FIG. 10 is a right end elevational view of the structure illustrated in FIG. 9, taken along the line 10-10 thereof and looking in the direction of the arrows;

FIG. 11 is a central elevational sectional view of a modified metering valve means and showing a fragmentary portion of the delay apparatus housing;

FIG. 12 is a horizontal sectional view of the modified metering valve embodiment illustrated in FIG. 11, taken along the line 1212 thereof and with the housing removed;

FIG. 13 is a side elevational view of the split metering valve sleeve employed in the embodiment of FIG. 11; and

FIG. 14 is a fragmentary view of the right end structure of FIG. 3, and showing the slide rod moved to the right, as viewed in FIG. 3, to permit air to bleed into the accumulator chamber.

The time delay apparatus of the present invention is especially adapted to be used in pressurized air circuits. The time delay apparatus of the present invention is adapted to be operatively connected between a device to be controlled, as for example, an air cylinder, and a conventional directional flow control valve for the purpose of timing-in and timing-out operations. The time delay apparatus of the present invention may also be used for other purposes as, for example, in an air line leading to a directional flow control valve to time the operation of that valve for timing the air-in and air-out periods of air flowing to the directional flow control valve.

Referring now to the drawings, the numeral generally indicates the time delay unit body which is made from any suitable material, as for example aluminum. As shown in FIGS. 3 and 6, the body 10 is provided on the left end thereof with a control chamber 11 and on the right end thereof with a free flow chamber 12. The chambers 11 and 12 are connected by the circular passageway or valve bore 13. The open outer ends of the chambers 11 and 12 are threaded as indicated by the numerals 14 and 15, respectively, for the reception of the pipe bushings 16 and 17. As shown in FIGS. 3, 6 and 8, the control chamber 11 is provided with a plurality of radially disposed, longitudinally extended, cored passageways indicated by the numerals 18. The free flow chamber 12 is also provided with a plurality of similar longitudinally extended passageways 19.

As shown in FIG. 3, the pressurized fluid metering means of the time delay unit is operatively mounted in the control chamber 11 and is generally indicated by the numeral 20. The flow valve is generally indicated by the number 21. The pressurized fluid metering means 20 includes the needle valve body 22 which is seated in the control chamber 11 and secured against outward movement by means of the retainer clip ring 23. The needle valve body 22 is provided with the slot 24 for the reception of a screw driver or the like for adjusting the position of valve body 22. As shown in FIGS. 3, 9 and 10, the needle valve body 22 is provided with the threaded needle valve bore 25 which is disposed at right angles to the longitudinal axis of the valve body 10, and which is adapted to be aligned with the stepped bore 26 formed in the valve body 10.

The fluid metering means includes a needle valve, generally indicated by the numeral 27, which is provided with an enlarged head portion 28, a cylindrical body portion 29 and an inner threaded end portion 30. The needle valve threaded portion 30 is threadably mounted in the bores 25 and 26 which are formed in the needle valve housing 22 and valve body 10, respectively. The head 28 of the needle valve is provided with a slot 31 for engagement by a screw driver or the like for adjusting the needle valve. The stepped needle valve bore 26 is provided with the enlarged portion 32 in which is mounted the sealing sleeve 33 for sealing engagement with the cylindrical smooth body portion 29 of the needle valve 27. The needle valve bore 26 is further enlarged as indicated by the numeral 34, and this portion 34 is threaded and is adapted to receive the gland member 35. The gland member 35 is provided with the inwardly extended annular flange 36 which is adapted to engage the outer end of the sealing member 33 and force it inwardly and into lateral sealing engagement with the needle valve body 29.

As shown in FIGS. 9 and 10, the needle valve body 22 is provided with a circular outer shape for seating in the cylindrically shaped control chamber 11. The needle valve body or housing 22 and the needle valve 27 are made from any suitable material as, for example, from stainless steel. As shown in FIGS. 3, 9 and 10, the needle valve body 22 is provided with an integral inwardly extended cylindrical shaft 37 through which is formed the axial metered fluid passage 38. The passage 38 extends inwardly into the needle valve body 22 and under the needle valve bore 25. The needle valve bore 25 is connected to the axial passage 38 by means of the the outer end of the flow valve 21.

4 orifice 39. As shown in FIG. 3, the needle valve 27 is provided with the conical nose or valve end 40 which is adapted to extend down into the control orifice 39 for metering the flow of pressurized fluid through the orifice 39 into the passage 38.

As shown in FIG. 3, the control chamber 11 is connected to the needle valve bore 25 by means of the inlet orifice 41. As shown in FIGS. 3 and 10, the needle valve body 22 is provided with the longitudinally extended bore 42 which extends inwardly into the valve body 22 from the inner side thereof and which is connected to the metered fluid passage 38 by means of the interconnecting passage 43. As shown in FIG. 3, a flexible or resilient sleeve 44, as for example, a rubber sleeve, is mounted in the bore 42 and normally blocks off communication between the passage 43 and the bore 42. The bore 42 communicates with the control chamber 11.

As shown in FIGS. 3, 4 and 5, the spring poppet or flow valve 21 comprises a cylindrical member which is adapted to be slidably mounted in the control chamber 11. The inner end of the flow valve 21 is reduced as indicated by the numeral 45 so as to provide the shoulder 45 which is adapted to engage the shoulder 47 formed at the junction of the control chamber 11 and the interconnecting passage or valve bore 13. The reduced flow valve end 45 is provided with the sealing O-ring 48 which engages the peripheral surface of the bore 13 to provide a sealing effect between the flow valve and the time delay body 10 when the flow valve is in the closed position shown in FIGS. 3 and 14.

The flow valve 21 is provided with the axial bore 49 which extends therethrough and in the outer end of which is slidably received the needle valve housing shaft 37. An O-ring sealing means 50 is mounted around the outer end of the shaft 37 to provide sealing between the shaft 37 and the flow valve 21. As shown in FIGS. 3 and 4, the fiow valve 21 is normally maintained in the closed or inoperative position by means of the spring 51 which is disposed around the shaft 37. The outer end of the spring 51 abuts the needle valve body 22 and the inner end of the spring 51 is seated in the annular recess 52 formed in FIG. 4 shows the spring 51 compressed and the flow valve 21 moved to the open position by the operation of the accumulator means.

As shown in FIGS. 3, 4 and 14, the time delay unit of the present invention includes an accumulator means, generally indicated by the numeral 53, which is adapted to move the flow valve 21 to the open position when a predetermined pressure differential is reached, between the pressure in the control chamber 11 and the pressure in the accumulator means 53. The accumulator means 53 includes the accumulator cylinder 54 which is open on the outer end thereof and which is provided with the inner end wall 55. The free flow chamber 12 is reduced at the inner end thereof as indicated by the numeral 56, so as to provide the shoulder 57. The accumulator cylinder inner end wall 55 is adapted to be seated against the shoulder 57 as shown in FIGS. 3 and 4. The outer end of the accumulator cylinder 54 is enclosed by means of the cap retainer generally indicated by the numeral 58. The accumulator cylinder 54 and retainer 58 are secured in the chamber 12 by means of the retainer snap ring 59.

The accumulator cylinder outer end cap 58 is provided on the inner end thereof with the cylindrical portion 60: which is provided with the chamber 61. The chamber 61 communicates with the accumulator cylinder 54 and tapers outwardly at the inner end thereof as indicated by the numeral 62 in FIG. 3. An O-ring sealing means 63; is provided around the cap cylindrical portion 60 to pro-- vide a sealing means between said portion and the ac-- cumulator cylinder 54. The inner end of the cylindercap 58 is indicated by the numeral 64.

As shown in FIGS. 3 and 4, the cylinder cap 58 is pro-- vided with the outwardly extended hub portion 65 through which is formed the axial bore 66. The outer end of a,

slide rod 67 is slidably mounted in the bore 66 and is provided with the O-ring sealing means 68. The inner end of the slide rod 67 is indicated by the numeral 70 and is slightly reduced in diameter and is separated from the enlarged outer end 67 by the outwardly extended transverse flange 69. As shown in FIGS. 3 and 4, the cylinder cap portion 60 extends inwardly into the accumulator cylinder 54 for approximately one-half the length thereof.

Slidably mounted in the inner end of the accumulator cylinder 54 is an accumulator piston generally indicated by the numeral 71. The accumulator piston 71 has a stepped cylindrical configuration which includes the inner portion 72 which is slidably mounted inside of the accumulator cylinder 54. A suitable O-ring sealing means 73 is mounted around the periphery of the accumulator piston portion 72 and engages the accumulator cylinder 54. Integrally formed on the front end of the accumulator piston portion 72 is the reduced annular portion 74 which extends through the axial bore 75 formed in the accumulator cylinder inner end wall 55.

The accumulator piston portion 72 is provided with the shoulder 76 on the inner end thereof and this shoulder is adapted to engage the inner side of the accumulator cylinder wall 55 when the piston 71 is moved to the left, as viewed in FIG. 4. An O-ring sealing means 77 is mounted in the shoulder 76 for sealing engagement with the end wall 55. A chamber is formed inside the piston 71 and it is indicated by the numeral 78 and may be termed a piston chamber. The piston chamber 78 coacts with the cap chamber 61 to form an accumulator chamber. The piston chamber 78 is open at the rear or outer end of the piston 71, as shown in FIGS. 3 and 4, and the end surface of the piston 71 is indicated in FIG. 4 by the numeral 79. FIG. 3 shows the piston 71 in the inoperative position, and in this position the rear end of the piston 71 is seated on the gasket or sealing means 103 which is disposed between the inner end 64 of the accumulator cylinder cap 58. The sealing means 103 could be disposed on either the piston 71 or the cylinder cap 58, or in a floating position therebetween.

As shown in FIGS. 3 and 4, the inner end of the accumulator piston 71 includes the integral cylindrical portion 80 which is of a diameter smaller than the portion 74 and which is provided with the axial bore 81 which communicates with the piston chamber 78. The slide rod inner reduced end 70 is slidably mounted in the piston bore 81. A suitable O-ring sealing means 82 is mounted around the inner end of the slide rod portion 70 and is adapted to engage the surface of the bore 81. As shown in FIG. 4, the inner end of the piston chamber 78 is provided with the reduced tapered portion 83 which slopes forwardly and inwardly and terminates at the inner end of the bore 81. The piston reduced portion 80 is provided at the outer end thereof with the transversely, outwardly extended peripherial flange 84 which seats against the inner end of the flow valve 21. The piston 71 is provided with the further integral reduced inner end or pilot shaft 85 which is adapted to be slidably received in the axial bore 49 in the flow valve 21. An O-ring sealing means 86 is opcratively mounted around the piston outer end 85 and engages the surface of the flow valve bore 49. As shown in FIGS. 3 and 4, the axial bore or passage 87 is formed through the piston end 85 and communicates the flow valve bore 49 and the piston bore 81.

The time delay unit of the present invention is adapted for two primary uses, namely, for timing-in and timingout operations. A timing-in operation in a fluid circuit for controlling the flow of pressurized fluid to a fluid cylinder or the like comprises a time delay interval during the fluid inlet period, and a free flow of the fluid from the cylinder upon reversal of flow of fluid initiated by a signal from a directional flow control valve in the circuit. A timing-out operation in a fluid circuit for controlling the flow of pressurized fluid from a fluid cylinder or the 6 like comprises a free flow of fluid during the fluid inlet period, and a time delay interval during the return flow of fluid from the cylinder, which return flow is initiated by a signal from a directional flow control valve in the circuit.

For a timingin operation the time delay unit is connected in a pressurized air system so that the pressurized air enters from the left side of the unit, as viewed in FIG. 3, to provide a time delay control over the air being supplied to an air cylinder or the like. In this timing-in arrangement the pressurized air is prevented from flowing to the air cylinder being operated until the time delay unit operates, and the timing starts from the pressure-in signal, that is, when the directional flow control valve in the system is operated to permit air flow to the time delay unit.

At the start of a timing-in operation the time delay unit would be in the condition shown in FIG. 3. The pressurized air would pass into the control chamber 11 and into the longitudinally extended cored passages 18 and thence through the inlet orifice 41 and into the needle valve bore 25. The air then flows past the needle valve nose 40 into the orifice 39 and the passage 38. The needle valve 27 would be set at a predetermined setting by means of the adjusting head 28. The air under pressure cannot pass out through the passage 44 and enter the bore 42 because the pressure of the air inside of the flexible sleeve 44 is equal to the pressure of the air entering the passage 38. The air under pressure flows through the passage 38 and into the bore 49 in the flow valve 21. The air under pressure continues to flow to the right, as shown in FIG. 3, and enters the accumulator piston passage 87 and engages the slide rod reduced end 74 and moves the slide rod to the right, to the position shown in FIG. 14. The air under pressure then passes around the end of the slide rod into the accumulator chamber portions 78 and 61, and when the air pressure builds up to a predetermined amount, it will react upon the inner surfaces of the accumulator piston 71.

The air in the accumulator first acts on the surface area inside of the accumulator piston 71 which is greater than the area of the flow valve 21 on which air under pressure in the control chamber 11 is operating, and consequently, when said predetermined air pressure is built up in the accumulator, the accumulator piston 71 will be moved to the left, as viewed in FIG. 3, and to the position shown in FIG. 4. The sealing means 1113 provides positive seating of the piston 71 to enclose the piston end area 79 whereby when the initial movement of the piston 71 is effected from the position shown in FIG. 3, the effective piston fluid working area will he suddenly increased when the rear area '79 is uncovered and a snapaction will be provided to the movement of the piston 71. When the accumulator piston '71 moves to the left as shown in FIG. 4, the flow valve 21 will be unseated to permit free flow of air under pressure from the control chamber 11 into the passage or valve bore 13, and thence into the free flow chamber 12 from whence it passes out of the delay unit by means of the longitudinal cored passages 19.

When air under pressure is admitted into the free flow chamber 12, it will engage the slide rod enlarged end 67 and move the slide rod to the closed position shown in FIG. 4. The seal 82 is brought into sealing engagement with the bore 31 to seal off the accumulator chamber and block off any reverse passage of air through the metering means. The passage of the air into the accumulator is thus blocked and uninterrupted free flow of air is permitted through the delay unit. The air passing through the metering means and engaging the reduced inner end of the slide rod will not create a force strong enough to move the slide rod to the right from the position shown in FIG. 4, because the larger area of the slide rod outer end 67 is being operated on by the same air pressure.

When the inward flow of pressurized air to the device being controlled is reversed upon a signal from the directional flow control valve in the air system, the air will flow through the time delay unit with a free flow action to the left, as viewed in FIG. 4. The exhausting air under pressure holds the flow valve 21 in the open position shown in FIG. 4. When the air pressure in the free flow chamber 12 drops a predetermined amount, the higher air pressure trapped in the metering means and accumulator will move the slide rod to the position shown in FIG. 14. As the air pressure drops in the control chamber 11, the higher air pressure in the metering means will be dumped into the control chamber 11 through the bore 42. The higher air pressure in the metering system will flex the sleeve 44 and discharge into the chamber 11. When the air pressure in the free flow chamber 12 drops a predetermined amount, the spring 51 will close the flow valve 21 and the delay unit will be in a condition for a further timing-in operation.

For a timing-out operation the delay unit would be connected in a pressurized air system to permit free flow of pressurized air into the delay unit from the right side thereof, as viewed in FIG. 4. The pressurized air would flow freely to the cylinder or other device being controlled because the flow valve 21 would be moved to the open position, to the left, as shown in FIG. 4, by means of the air pressure operating on the right end of flow valve 21. The inlet orifice 41 is closed by the flow valve 21 when it is in the open position shown in FIG. 4. When the cylinder or other device has been operated by the free flow of pressurized air, an exhaust signal will be given by the directional flow control valve in the system and the metering means will operate to provide a timing-out delay period. All of the air around the accumulator cylinder 54 will be exhausted to the atmosphere and all of the air between the directional flow control valve and the flow valve 21 will be exhausted. The spring 51 will coact with the pressurized air trapped between the air cylinder and the time delay unit to move the flow valve 21 to the right, to the closed position as shown in FIG. 3. The air pressure is thus removed from the outer large end 67 of the accumulator slide rod and the pressurized air trapped in the control chamber 11 will operate on the reduced end 70 of the slide rod to move it backwardly to the accumulator chamber to permit the trapped pressurized air to enter the accumulator chamber. The air pressure then builds up in the accumulator chamber to the point where the piston 71 will be moved to the left as viewed in FIG. 3 so as to open the flow valve 21 to terminate the timing-out delay period. The pressurized air is then exhausted from the air cylinder in a free flow and the directional flow control valve may be operated to initiate a new timing-out sequence.

FIGS. 11, 12 and 13 illustrate a modified needle valve or metering means for use in the time delay unit of the present invention, and the parts thereof which are similar to the parts of the first needle valve embodiment are marked with the same reference numerals followed by the small letter a. In this modified needle valve construction the needle valve bore is indicated by the numeral 89. Seated in the bore 89 is a calibrated sleeve 90 which is provided with a vertical or longitudinally extended slot 91. The slot 91 is positioned so as to communicate with the inlet orifice 92 which is in communication with the control chamber 11a. The inlet orifice 92 may be provided with a suitable filter 93, for example, a sintered metal filter.

The amount of pressurized air flowing into the valve chamber 89 through the slot 91 is controlled by the valve rod 94. The valve rod 94 is provided on the lower end thereof with the sealing means 95. The upper end of the valve rod 94 is threadably mounted in the adjusting knob 96. The adjusting knob 96 is provided with the screw driver slot 97 and is rotatably mounted in the retainer 98 which is threadably mounted in the stepped bore 99 in the delay unit body a. A retainer sleeve 100 is mounted in the reduced inner end of the stepped bore 99 and it operates to hold the calibrated sleeve in place. An O-ring sealing means 102 is mounted on the inner end of the rotatable valve adjusting knob 96.

It will be seen that the valve rod 94 may be moved inwardly or outwardly by rotating the adjusting knob 96. As shown in FIG. 11, the valve rod 94 may be moved inwardly to reduce the effective operating open area of the slot 91 and reduce the amount of pressurized air passing into the orifice 3911. It will be seen that the wall thickness of the sleeve 90 is small so as to provide a short passageway through the slot 91, whereby the air under pressure in control chamber 11a has only to travel a short distance in order to enter the metering valve bore 89. The filter 93 and the short passageway through slot 91 function to prevent passage of dirt into the metering valve. A time delay unit provided with the metering valve structure of FIGS. 11, 12 and 13 would operate in the same manner as described hereinbefore for the embodiment of FIGS. 1 through 10.

While it will be apparent that the preferred embodiments of the invention herein disclosed are well calculated to fulfill the objects above stated, it will be appreciated that the invention is susceptible to modification, variation and change without departing from the proper scope or fair meaning of the subjoined claims.

What I claim is:

1. A time delay apparatus for controlling the flow of pressurized fluid in a fluid circuit, comprising: a body having a control chamber, a free flow chamber, a valve bore connecting said chambers; a flow valve in said control chamber for engagement with said valve bore for controlling fluid flow therethrough; means for normally maintaining said flow valve in a closed position in seating engagement with said valve bore; accumulator means in said free flow chamber for unseating and moving said flow valve to an open position; pressurized fluid metering means in said control chamber for admitting a metered flow of said fluid into said accumulator means for operating the same in predetermined timed cycles for timing the opening and closing of said flow valve to provide a delayed flow of pressurized fluid through the chambers when the fluid moves through the valve-bore in one direction; and said flow valve being movable slidably relative to the accumulator means to the open position to provide a free flow of pressurized fluid through the chambers when the fluid moves through the valve bore in the opposite direction.

2. A time delay apparatus for controlling the flow of pressurized fluid in a fluid circuit, comprising: a body having a control chamber, a free flow chamber, and a valve bore interconnecting said chambers; a flow valve in said control chamber for controlling fluid flow therethrough; means for normally maintaining said flow valve in a closed position in seating engagement with said valve bore to block flow of fluid from said control chamber into said free flow chamber; an accumulator cylinder mounted in said free flow chamber; a piston having one end slidably mounted in said cylinder and the other end movable slidably relative to said flow valve; said flow valve being movable relative to the accumulator piston to the open position, to provide a free flow of pressurized fluid through the chambers when pressurized fluid enters the time delay apparatus through the free flow chamber and moves through the valve bore into the control chamber; said piston having means engageable with said flow valve when the piston is moved from a first position in said cylinder by pressurized fluid to a second position to unseat said flow valve and move it out of said valve bore to provide free flow of fluid from said control chamber into said free flow chamber; and, pressurized fluid metering means in said control chamber for controlling the rate of flow of pressurized fluid into the accumulator cylinder.

3. A. time delay apparatus for controlling the flow of pressurized fluid in a fluid circuit, comprising: a body having a control chamber, a free flow chamber and a valve bore interconnecting said chambers; a flow valve in said control chamber for controlling fluid flow therethrough; means for normally maintaining said flo w VZillVC in a closed position in seating engagement with said valve bore to block flow of fluid from said control chamber into said free flo-w chamber; an accumulator cylinder mounted in said free flow chamber; a piston having one end slidably mounted in said cylinder and the other end engageable with said flow valve; said piston being movable from a first position in said cylinder by pressurized fluid to a second position to unseat said flow valve and move it out of said valve bore to provide free flow of fluid from said control chamber into said free flow chamber; a fluid passage interconnecting said accumulator cylinder and said control chamber; pressurized fluid metering means in said control chamber for controlling .the rate of flow of pressurized fluid from said control chamber into said fluid passage; and, a slide valve means mounted in said accumulator cylinder for controlling the flow of pressurized fluid from said fluid passage into said accumulator cylinder.

4. A time delay apparatus for controlling the flow of pressurized fluid in a fluid circuit, comprising: a body having a control chamber, a free flow chamber, and a valve bore interconnecting said chambers; a flow valve movably mounted in said control chamber; a spring means for biasing said flow valve into closing engagement with said valve bore to block the flow of fluid from said control chamber into said free flow chamber; an accumulator cylinder mounted in said free flow chamber; a piston having one end slidably mounted in said cylinder and the other end engageable with said flow valve; said piston being movable from a first position in said cylinder by pressurized fluid to a second position to move said flow valve out of said valve bore to open said Valve bore to provide free flow of fluid from said control chamber into said free flow chamber; a pressurized fluid metering means housing mounted in said control chamber; a metering valve chamber in said metering means housing; a passage connecting said metering valve chamber with said con-trol chamber; a passage formed through said flow valve; a passage in said metering means housing connecting the passage in said flow valve to the metering valve chamber; a passage through said piston and connecting passage in said flow valve to said accumulator chamber; and, a metering valve in said metering valve chamber for controlling the rate of flow of pressurized fluid from said control valve chamber and through said passages to said accumulator cylinder.

5. A time delay apparatus for controlling the flow of pressurized fluid in a fluid circuit, comprising: a body having a control chamber, a free flow chamber, and a valve bore interconnecting said chambers; a flow valve movably mounted in said control chamber; a spring means for biasing said flow valve into closing engagement with said valve bore to block the flow of fluid from said control chamber into said free flow chamber; an accumulator cylinder mounted in said free flow chamber; a piston having one end slidably mounted in said cylinder and the other end engageable with said flow valve; said piston being movable from a first position in said cylinder by pressurized fluid to a second position to move said flow valve out of said valve bore to open said valve bore to provide free flow of fluid from said control chamber into said free flow chamber; a pressurized fluid metering means housing mounted in said control chamher; a metering valve chamber in said metering means housing; an axial bore formed through said flow valve;

said other end of said piston having a portion slidably mounted in the inner end of the axial bore in said flow valve; an axial bore formed through said piston and connecting the bore in said flow valve to said accumulator chamber; a shaft entended from said metering means housing and having the outer end thereof slidably engageable in the outer end of the axial bore in said flow valve; a passage formed through said shaft and housing and connecting said metering valve chamber and the axial bore in said flow valve; a metering valve in said metering valve chamber for controlling the rate of flow of pressurized fluid from said metering valve chamber and through said passage and axial bores to said accumulator cylinder; and, a passage connecting the control chamber with the metering valve chamber.

6. A time delay apparatus as defined in claim 5 including, a slide rod mounted in said accumulator cylinder and having one end engageable in the axial bore in said piston for controlling the flow of pressurized fluid into said accumulator cylinder.

7. A time delay apparatus as defined in claim 6, wherein: the other end of said slide rod extends outwardly of said accumulator cylinder and is engageable by pressure in said free flow chamber for moving said one end of the slide rod into the axial bore in said piston and blocking the flow of pressurized fluid therethrough.

8. A time delay apparatus as defined in claim 5, wherein: said metering valve comprises an adjustably mounted needle valve for controlling the flow of pressurized fluid through the passage connecting the control chamber with the metering valve chamber.

9. A time delay apparatus as defined in claim 5, wherein: said metering valve comprises a slotted sleeve mounted in the metering valve chamber with the slot providing communication between the metering valve chamber and the passage connecting the metering valve chamber with the control chamber, and a valve member adjustably mounted in the slotted sleeve to control the flow of pressurized fluid into the slot and into the metering valve chamber.

10. A time delay apparatus as defined in claim 5, wherein: said metering valve chamber is connected by a second passage to said control chamber, said second passage being normally closed by a flexible closure member whereby when the pressure of the fluid in the control chamber is lower than the pressure of the fluid in the metering valve chamber, the closure member will open to exhaust the pressurized fluid in the metering valve chamber.

11. A time delay apparatus as defined in claim 5, wherein: said accumulator cylinder includes a cylinder cap for enclosing one end of the cylinder; a sealing means disposed between said cylinder cap and engageable by the accumulator piston when it is in said first position in said cylinder, whereby the piston fluid pressure eflective working area is suddently increased after the initial movement of the accumulator piston from the first position when it is unseated from said sealing means.

References Cited by the Examiner UNITED STATES PATENTS 2,676,612 4/1954 Stevenson 137-490 X 2,680,453 6/1954 Prijatel 1374-90 2,774,373 12/ 1956 Frevet 137-49O FOREIGN PATENTS 1,261,701 4/1961 France.

MARTIN P. SCHWADRON, Acting Primary Examiner.

M. CARY NELSON, Examiner. 

1. A TIME DELAY APPARATUS FOR CONTROLLING THE FLOW OF PRESSURIZED FLUID IN A FLUID CIRCUIT, COMPRISING: A BODY HAVING A CONTROL CHAMBER, A FREE FLOW CHAMBER, A VALVE BORE CONNECTING SAID CHAMBERS; A FLOW VALVE IN SAID CONTROL CHAMBER FOR ENGAGEMENT WITH SAID VALVE BORE FOR CONTROLLING FLUID FLOW THERETHROUGH; MEANS FOR NORMALLY MAINTAINING SAID FLOW VALVE IN A CLOSED POSITION IN SEATING ENGAGEMENT WITH SAID VALVE BORE; ACCUMULATOR MEANS IN SAID FREE FLOW CHAMBER FOR UNSEATING AND MOVING SAID FLOW VALVE TO AN OPEN POSITION; PRESSURIZED FLUID METERING MEANS IN SAID CONTROL CHAMBER FOR ADMITTING A METERING FLOW OF SAID FLUID INTO SAID ACCUMULATOR MEANS FOR OPERATING THE SAME IN PRESSURIZED FLUID THROUGH THE CHAMBERS THE OPENING AND CLOSING OF SAID FLOW VALVE TO PROVIDE A DELAYED FLOW OF PRESSURIZED FLUID THROUGH THE CHAMBERS WHEN THE FLUID MOVES THROUGH THE VALVE BORE IN ONE DIRECTION; AND SAID FLOW VALVE BEING MOVABLE SLIDABLY RELATIVE TO THE ACCUMULATOR MEANS TO THE OPENING POSITION TO PROVIDE A FREE FLOW OF PRESSURIZED FLUID THROUGH THE CHAMBERS WHEN THE FLUID MOVES THROUGH THE VALVE BORE IN THE OPPOSITE DIRECTION. 